1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having a structure that can improve contrast by reducing reflective brightness from external light.
2. Description of the Related Art
A plasma display panel (PDP) displays images by exciting phosphor layers formed in a predetermined pattern with ultraviolet rays that are generated from a glow discharge. The glow discharge occurs when a predetermined voltage is applied to electrodes formed is a closed space where a discharge gas is filled.
PDPs can be classified into direct current PDP, alternating current PDP, and hybrid PDP according to driving methods. PDPs can be further classified into those having a minimum of two electrodes and those having a minimum of three electrodes. A direct current PDP includes address electrodes that increase addressing speed by performing an address discharge and a sustain discharge separately. Alternating current PDPs can be divided into those with an opposing discharge electrode structure and those with a surface discharge electrode structure according to the disposition of the electrodes. In the opposing discharge electrode structure, a discharge occurs in a direction perpendicular to the PDP by applying a potential difference to two sustain electrodes on different substrates. In the surface discharge electrode structure, a discharge occurs on one surface of a substrate by having both sustain electrodes on the same substrate.
In PDPs, reflective brightness of external light is an important factor affecting performance. Reflective brightness is from light external to the PDP that reflects off the display of the PDP during operation of the PDP. The more reflective brightness there is, the poorer the image quality becomes. The brightness and contrast of the PDP are reduced if the reflective brightness is increased. The reflective brightness can be further increased if a white pigment, such as TiO2, is added to a barrier rib to effectively reflect light emitted from a phosphor layer. Therefore, there is a need to reduce the reflective brightness. A conventional method of preventing the reflection involves placing a black stripe that can block external light on a non-discharge region of the PDP. A problem with incorporating the black stripe into the design of a PDP is that several extra manufacturing steps are required to make a PDP having the black stripe. For example, the black stripe material must be applied or deposited on the structure somehow. Then the black stripe material has to be patterned. All of these extra steps can be extremely expensive in a manufacturing production environment. Therefore, what is needed is a more effective solution to the reflection of external light problem that both results in an effective PDP structure that is also inexpensive, simple and easy to make.